Apparatus for forming sheet metal



Nov. 5, 1946. J. s. NIELSEN 2,410,676

APPARATUS FOR FORMING SHEET METAL Filed Oct. 16, 1943 James S, N/e/senPatented Nov, 5, l

.UN'ITED' STATES 2,410,875 I APPARATUS FOR FOG SHEET EAL lanes 8.Nielsen, Stow, @hlo, assignor to ts "i year Aircraft Got-partition,Akron, Ohio, a-corporationoi Dela Application October iwitdt, Serial No.506,474 I This invention relates to apparatus for form 5 Claims. (Cl.

ing sheetmetal, and, moreparticularly, is concharacteristic that onlyone die is needed, instead of .a mating male and female die, with therubber platen serving to apply relatively high pressure over the entirearea of a piece of sheet metal positioned over the forming die. However,in forming flanges on sheet metal by apparatus of this type, and,specifically, where such flanges are curved or contoured, as is so oftenthe case, it has usually been necessary to partially form the sheetmetal with the rubber platen apparatus,

and follow this forming operation with extensive and laborioushand-finishing operations or other machine-finishing operations.

It is the general object of this invention to avoid and overcome theforegoing and other objections to and dlmculties of known rubberplaten-press apparatus and the like, by the provision of improved meansfor facilitating forming curved and contoured edges on sheet metal in asingle rubber pressing operation.

Another object of the invention is the provision of improved apparatusof relatively inexpensive, readily operated'character which facilitatesforming contoured flanges and'the like on sheet metal during a rubberplaten-press sheetmetal-forming operation,

Another object of the invention is the provision of apparatus of thecharacter described and wherein an overhanging sheet metal edge isgripped by adjustably actuated clamping plates to provide a progressivebending and stretching of the sheet metal edge and a progressiveslipping of the sheet metal edge out from between the clamping means.

The foregoing objects of the invention, and

adjustably clamping the shaping means againsteach other on oppositesides of the overhanging edge, and means for efiecting relative movementbetween the shaping means and the support to progressively bend theoverhanging edge around the support with a progressive slipping oi theoverhanging edge out from between the shaping means.

For a better understanding of the invention, reference should be had tothe accompanying drawing, wherein Figure 1 is a vertical cross-sectionalview through typical apparatus incorporating the invention (with thesectional view being taken on line i-+l of Figure 2-) and Figure 2 is aplane view of a portion of the apparatus as taken substantially on line2-2 of Figure 1.

Having specific reference to the drawing, the numeral l0 indicatesgenerally a bed or platen adapted to mount thereon a support or die itfor a piece of sheet metal It, with the sheet metal being supported soas to have an edge portion overhanging the die or support It. Theoverhanging edge of the sheet metal it is adapted to be adjustablygripped by contoured shaping means, indicated as a whole by the numeralit, which conveniently take the form, as illustrated, of a pair ofopposed metal shoes, draw-blocks, or dies in the form of plates it andI8, having one or more aligning pins 20. The plates it and it of theshaping means are adjustably secured together by any suitable means,such as threaded studs 22, secured in the plate It, extending throughholes in the plate it, and receiving thumb nuts 2%.

Some means are provided for mounting the shaping means It so that themetal-gripping edges thereof can have relative movement with respect tothe support 82 for the sheet metal. One particularly practical way ofachieving the desired result is to form the plate member It of a wedgeshape and with the plate tapering to a relatively thin edge adjacent thedie or support l2. When the plate It is shaped in this way. thecontoured shaping means I5 have bodily movement as a whole of pivotingcharacter from the full-line-position shown to beyond the dotted-linposition shown. The movement of the contoured shaping means from thefull to the dotted-line position is achieved by any desired means, forexample by the use of a rubber platen including a rubber body 30supported in the metal platen member 82. The rubber body 30 not onlyserves to force the sheet metal 14 into shaped contact with the die orsupport l2 but also serves to-apply pressure to the top plate It of thecontoured shaping means I 5, and this pressure causes the contouredshaping means I! to tilt with a.plvotingactioniromthemll-linetoandbeyond the dotted-line P itico.

During the movement or the contoured shaping means I from the rull-lineposition to and beyond the dotted-line position, the overhanging edge oithe sheet metal gripped by the contoured shaping means progressivelyslips out from between the shaping means to cause a progressive bendingand a simultaneous progressive stretchin! of the overhanging sheet metaledge, so that the edge oi the sheet metal is contoured and shaped to theparticular form desired. From the drawing it will be recognized that alongitudinally curved flange can be formed on the sheet metal edge, andthe flange can extend at any desired angle with respect to the main bodyoi the sheet metal.

From the foregoing, it will be recognized that the objects of theinvention have been achieved by the provision of simplified and improvedmeans and method for forming sheet metal and particularly for shapingcurved and contoured flanges on sheet metal parts during a rubberplaten-pressing operation. The flanges are formed to the desired shapesand contours substantially without spring-back and to substantiallyeliminate the necessity for subsequent hand-forming or additionalshaping operations. 01 course, any number of contoured shaping means,such as particularly illustrated, can be employed, and the contour oithe shaping means can be widely varied to suit any specific requiredshaping operation.

While, in accordance with the patent statutes, the invention has beenspecifically illustrated and described, it will be understood that theinvention is not limited thereto or thereby, but that the scope of theinvention is defined in the appended claims.

I claim:

1. Apparatus for shaping sheet metal and including a die support, a dieon the support, said die carrying and positioning the sheet with anoverhanging edge, multi-part contoured shaping means adapted to grip theoverhanging edge the sheet, the lowermost part of said shaping meanshaving a wedge shape in vertical section and resting loosely on the diesupport in pivotal relation therewith, said shaping means beingpivotally supported on the die support at a point spaced from the dieand to the underside of the plane of the overhanging edge, a rubberblock, and means for forcing the rubber block against the upper surfaceof the sheet to form it into the die and simultaneouly to rock theshaping means about'the pivotal support progressively to bend andstretch the overhanging edge.

2. Apparatus for forming sheet metal, comprising a die support, a dieresting on said support and having straight or substantially straight aswell as curved circumferential contour portions, said die carrying thesheet to be formed with its edges overhanging, rubber platen meansmovable to and from the die, and supplementary gripping means,independent of the overall configuration oi the main die,- used onlyadjacent said curved die portions and coniorming to the contoursthereof, the outer bottom portion of said ripping means being in slidingand tilting contact with said die support and its inner portion being inslidable and adjustable clamping engagement with the metal sheet, sothat the straight edge portions oi said sheet are flanged directly bythe rubber platen, but which acts upon the curved portions by means ofsaid gripping means in order to obtain smooth wrinkleless flanges.

3. Apparatus for forming sheet metal, comprising a die support, a dieresting on said support and having straight or substantially straight aswell as curved circumferential contour portions. said die carrying thesheet to be formed with its edges overhangin rubber platen means movableto and from the die, anda. supplementary, relatively short, tiltablegripping die independent of the overall configuration oi the main dieand adjustable for various sheet thicknesses, in sliding contact withsaid die support and in slidable engagement with only the curved edgeportions of the metal sheet in order to prevent wrinkling of said curvedportions.

4. Apparatus for forming sheet metal, com-,

said first mentioned die and said rubber platen means for fianging onlythe curved portions of said metal sheet, said supplementary die beingwedge-shaped in cross section with its thin portion gripping the sheetedge and with its wide portion resting in sliding and tilting relationon said die support.

5. Apparatus for forming sheet metal, comprising a die support, a dieresting on said support and having straight or substantially straight aswell as curved circumferential contour portions, said die carrying thesheet to be formed with its edges overhanging, rubber platen meansmovable to and from the die, and a separate supplementary flanging diein cooperation with the die and said rubber platen means, said flangingdie including means for clamping with adjustable pressure on theoverhanging edge of the sheet adjacent the curved portions of the die,that portion of the fianging die remote from the sheet resting intilting and sliding relation on the die support, so that movement of therubber platen means against the die will flange the overhanging sheetedge against the straight portions of the die and will simultaneouslymove the fianging die with a tilting and wiping movement to form acurved flange in the sheet with out wrinkling the curved flange.

JAMES S. NIEISEN.

